the effects of continuous vs. intermittent caloric restriction on fat los

Conditions: Obesity

Summary: the purpose of this research study examines fat mass loss using a continuous calorie reduction protocol versus continuous caloric restriction interspersed with "diet refeeds" and "diet breaks" over 12 weeks.

in order to lose weight, an individual must sustain an energy deficit (whereby caloric intake is significantly lower than expenditure) over time. however, a rich base of evidence suggests that weight loss often results in a decreased metabolic rate. this decrease, likely the result of a number of physiological and behavioral mechanisms, makes the continuation of weight loss more difficult as well as increases the likelihood of weight regain, or the "rebound" effect (1, 2). one proposed method of promoting the retention of a higher metabolic rate through a period of caloric restriction, and therefore preventing the regain of excess weight after energy restriction is discontinued, is the use of intermittent rather than continuous caloric restriction. intermittent energy restriction (ier) involves undulating one's energy intake throughout a dieting period as opposed to sustaining a continuous energy deficit. research in overweight and obese individuals has shown that periods of moderate caloric restriction interspersed with periods of consuming a diet in balance with one's daily energy needs (caloric maintenance) is at least comparable to continuous energy restriction in terms of weight and fat loss outcomes (3) and may even bestow unique benefits by promoting greater retention of fat-free mass and a higher metabolic rate (4). however, to date, no published research has examined continuous caloric restriction compared to intermittent energy restriction (diet breaks and diet refeeds) in females only with obesity.

Eligibility criteria:
inclusion criteria: * adults aged 18-65 years of age, 2) females only, 3) all ethnicities 4). must reside in horry county, south carolina, 5) have a bmi of \> 30-45 kg/m2 6) weight stable for the last 3 months 7). exercise less than 150 minutes of physical activity per week) 8. have access to an apple® iphone or android® smart phone. exclusion criteria: * adults who are physically active greater than 150 minutes per week, participants who were unwilling or unable to attend testing sessions between 6 am and 12 pm, participants planning to take holidays and/or work-related travel during the study period (challenges adherence to the diet, and interferes with testing session scheduling, participants who have lost greater than 10 pounds in the last 3 months, participants has stated an immunodeficiency disorder, kidney disease, heart attack within the last 3 months, has known dementia, brain cancer, current eating disorders, history of significant neurological or psychiatric disorder or any other psychological condition impacting their decision making, currently taking dietary supplements that could profoundly modify metabolism or body weight, has undergone major surgery, less than 4 weeks prior to enrollment in the study, undergone bariatric surgery \<12 months prior to starting the study, or diagnosis of type 1 diabetes. although not anticipated for this study population, women cannot be or suspect they may be pregnant.

Keywords: weight loss, telehealth, health coaching, diet breaks